diff --git a/src/object/class.cpp b/src/object/class.cpp
index 6a839fb2..60a803f9 100644
--- a/src/object/class.cpp
+++ b/src/object/class.cpp
@@ -205,7 +205,7 @@ namespace
       std::vector<entry>::const_iterator p
           = boost::detail::lower_bound(start, finish, id);
 
-      if (p == finish && p->key != id)
+      if (p == finish || p->key != id)
       {
           string report("extension class wrapper for base class ");
           (report += id.name()) += " has not been created yet";